The present invention relates to packaged integrated circuit (IC) devices and more particularly to packaged IC devices assembled using lead frames.
In order to prevent internally generated heat from damaging an IC die in a packaged IC device, the device may include a heatsink that is mounted on top of the die, where the top side of the heatsink is exposed at an outer surface of the packaged device. During the molding or encapsulation phase of the device assembly process, the molding tool applies force to the device sub-assembly to prevent liquid molding compound from seeping between the top side of the heatsink and the bottom surface of the top mold chase of the molding tool and thereby covering some or all of the top side of the heatsink with molding compound, which would inhibit the packaged device's heat dissipation capabilities. Unfortunately, the compressive force applied by the molding tool during the encapsulation phase can result in physical damage, such as cracking, to the IC die.